Study links obesity and Alzheimer's

PHILADELPHIA, Dec. 30 (UPI) -- Researchers said Friday they have shown that being extremely overweight or obese ups the risk of developing Alzheimer's.

The researcher team -- comprised of scientists from the United States and Australia -- said it has found a strong correlation between body mass index and high levels of beta-amyloid, the sticky protein substance that builds up in the Alzheimer's brain and is thought to play a major role in destroying nerve cells and in cognitive and behavioral problems associated with the disease.

The researchers are from the Farber Institute for Neurosciences at Thomas Jefferson University in Philadelphia and Edith Cowan University in Joondalup, Western Australia.

"We looked at the levels of beta-amyloid and found a relationship between obesity and circulating amyloid," says Sam E. Gandy, director of the Farber Institute for Neurosciences. "That's almost certainly why the risk for Alzheimer's is increased," said Gandy, who is also professor of neurology, biochemistry and molecular biology at Jefferson Medical College of Thomas Jefferson University. "Heightened levels of amyloid in the blood vessels and the brain indicate the start of the Alzheimer's process."

The findings appear this month in the Journal of Alzheimer's Disease.

Gandy said that evidence has emerged over the last five years that many of the conditions that raise the risk for heart disease -- such as obesity, uncontrolled diabetes, hypertension and hypercholesterolemia -- also increase the risk for Alzheimer's.

Exactly how such factors make an individual more likely to develop Alzheimer's remains unclear.